1. Technical Field
This invention relates to an apparatus for use in exercising the abdominal muscles and more particularly, to an inflatable exercise device which is primarily useful for exercising the abdominal muscles of the exerciser by sit-up type exercises.
2. Background Information
A flattened stomach is not only aesthetically desirable, but also indicates that an individual possesses the abdominal strength necessary to avoid some types of low back pain. A flattened stomach is an objective of the most common types of exercise programs to strengthen and decrease the size of the abdominal area to promote good health and fitness. Sit-up type exercises which are also known more properly as the abdominal curl are one of the most common exercises which one can perform to decrease the size and contour of the abdomen. Other related exercises which are designed to strengthen the abdominal muscles are frequently related to the sit-up type exercise, but are frequently more difficult to perform and provide desirable results in decreasing the size and contour of the abdominal area.
While there have been many different types of abdominal exercising devices in the field, a number of such devices produce results which do not necessarily strengthen the abdominal muscles but more powerful hip and thigh muscles which attach to the lumbar spine area and to the rear of the pelvis and hip bones. When such muscles contract not only does the rectus muscle of the abdomen work with little effort but the other muscles rotate the pelvis forward thus creating the occurrence of increased lower back pain which contributes to poor mechanical alignment and undesirable upright posture of the exerciser. Normally, in the performance of conventional sit-up exercises, the feet are projected horizontally or locked under a stationary object to obtain desired leverage. The stronger leg muscles substitute for the abdominal muscles which are not more positively strengthened by the sit-up type exercise. It is preferred that the legs be in a bent position during the sit-up exercise rather than projecting horizontally in locked position.
U.S. Pat. No. 4,752,067 to D. J. Colonello entitled Apparatus For Use In Exercising The Abdominal Muscles relates to a specially shaped rigid exercise device upon which the exerciser lies to perform the exercise wherein the pelvis is cradled in a pelvic basin portion of the device while the lumbar spine is supported by a longitudinal support cushion, the angulation of the interface area between the two body portions being arched convexly to support the anatomical transition between the lower vertebrae of the spine called the sacrum region and the lumbar spine. The rigid solid contoured device of this patent defines a longitudinal axis of symmetry for receiving the buttocks and pelvis of the exerciser, such portion being elliptical in shape with the perimeters smoothly sloping upwardly except for the area of transition of the lumbar support portion. Such device has been marketed under the Trademark, ABDOMENIZER, and being a solid rigid structure having considerable size, cannot be readily transported from place to place for use in different locations, such as while traveling or between several locations in the essentially same locale. While such exercise device has been found to be particularly beneficial to the user, it does not lend itself to comfortably supporting the user while exercising to obtain the same desirable results of abdominal strengthening. While the rocker portion is contoured to fit the lumbar spine area of the user, the widely different back and side configurations of the exerciser must conform to the rigid structure and may or may not be most comfortably supported since no cushioning effect is either directly or indirectly provided to the user by this type of exerciser.
U.S. Pat. No. 4,132,228 to Green discloses a comfort support seat assembly designed to alleviate discomfort of persons who are required to sit for long periods. Such seat cushion is intended to provide even distribution of the gluteal region with pressure relief to assist in alleviating discomfort for long term sedentary positions.
In addition, U.S. Pat. No. 4,230,099 to Richardson and U.S. Pat. No. 4,848,472 to Lindley, both relate to rigid exercise apparatus upon which the exerciser rests one's hips and feet while lying on a flat surface such as a floor while the user oscillates or rotates his body to stretch or relax the back muscles.
U.S. Pat. No. 1,904,039 to Bruder also relates to an essentially rigid body exercising apparatus having elongated ridge members forming a convex curve which substantially corresponds to the natural lumbar curve of the human spine.
None of the aforesaid devices provides significantly distinct comfortable support of the exerciser while performing sit-up type exercises wherein the exerciser is provided with both a pneumatic support of one's body portion out of contact with the underlying supporting surface and wherein a pneumatic tilt effect is automatically provided for upward sit-up assist in performing such exercises.